• Title/Summary/Keyword: capacity ratings

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Cross-Border Asset Pledgeability for Enhanced Financial Stability

  • Choi, Gongpil
    • East Asian Economic Review
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    • v.24 no.1
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    • pp.89-124
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    • 2020
  • Even with the sizable Foreign Exchange (FX) holdings and good credit ratings of its top assets, Asia remains vulnerable to various shocks. This paper highlights the limited cross-border asset pledgeability as a significant factor for the lingering vulnerability in Asia. The dichotomy in asset holdings between pledgeable FX and non-pledgeable domestic assets in major economies in Asia has been the source of increasing stabilization costs as well as weakened market momentum in the region. Specifically, the peculiar feature of asset holdings in Asia reflects seriously deficient cross-border asset pledgeability that is left unaddressed. Asset pledgeability contributes toward financial stability via three channels: 1) capital market development by recognizing the role of collateral, 2) increased shock absorption capacity via collateral management, 3) and the newly activated safe asset provision. Therefore, it is crucial to go beyond the usual market development strategy and expand the overall asset pledgeability in the region that has remained unduly depressed.

A Study on the Modeling and Analysis of the Micro-Grid (마이크로그리드의 모델링 및 해석에 관한 기초 연구)

  • Son, Kwang-M.;Lee, Kye-B.
    • Proceedings of the KIEE Conference
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    • 2006.07a
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    • pp.533-534
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    • 2006
  • Micro-source units having power ratings in thousands of watts can provide power quality with higher reliability and efficiency than the conventional large scale units. This paper develops switching level model of micro-source and studies the characteristics of the micro-grid consisting of multiple micro-sources and interfaced with electric power system. The developed model adopts the space vector PWM to fully utilize the capacity of inverter. The interaction of the grid connected micro-sources and the characteristics of the control system parameters are investigated. Micro-sources and micro-grid are implemented using PSCAD/EMTDC. Simulation results show that the proposed model is efficient for studying micro-grid system.

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Power System Simulation in Seoul matropolitain subway Line-6 system (서울 지하철 6호선에 대한 전력계통 시뮬레이션)

  • Lee, Tae-Shik;Moon, Young-Hyun;Sung, Soo-Young;Yoon, Kap-Koo
    • Proceedings of the KIEE Conference
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    • 1993.07a
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    • pp.137-139
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    • 1993
  • This paper details methods used to verify the adquacy of a dc traction power supply for design in Seoul matropolitain subway Line-6 system. Examples of the approach are given for a major subway presently under construction. The performance of trains operating at maximum system design capacity is modelled using a train simulation program. Using a dc network analyser program, the maximum train operating timetable, and a model of the ac and dc electrical suppy system, the electrical performance of the entire system can be modelled over a 24-hour period. The results of this analysis are used to determime: train voltage at a level sufficient to ensure train schedules: adequacy of traction transformers, rectifier, and switchgear ratings; sizes of the overhead contact systern conductors, and ac and de feeder cables: and power and energy demands at the utility company's supply points for inital and final timetable operations.

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A Study on the Legal Application for Sport Pilot Certificate in Korea (스포츠조종사 자격증명의 국내 적용에 대한 연구)

  • Noh, Yo-Sup;Kim, Young-Hoon
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.13 no.3
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    • pp.43-60
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    • 2005
  • In september 2004, a new pilot certificate scheme referred to as Sport Pilot Certificate was declared official and standardized in the US. The designation of Light-sport aircraft and the details of the relevant pilot certificate policy was announced out of the perception that a new regulation is required to be applied whereby the limitations on the manufacturing process enhancements and current aviation rules are considered the triggering factors. US Federal Aviation Regulation retains a comprehensive range of airworthiness certificates and aircrafts are managed systematically in accordance with FAR 21, 103. The airworthiness are further segregated into sub categories, which allows differentiated management. Korean Aviation Law classify aircraft into five different categories and powered air vehicle that weighs more than 150kg(19liters fuel capacity) for one seat, 225kg for two seats(38liters fuel capacity) while the systems that fall under a specific mass threshold level are known as ultralight vehicle. The research discusses the policy of the sport pilot certificate and the light-sport aircraft ratings announced official by the Federal Aviation Administration in an intuitive fashion with the analysis of the operations providing the evidence as to the viability of adopting the policy in local grounds. Based on the findings, the report discusses the case for introducing the light-sport aircraft and make recommendation on a strategy of applying the policy in Korea with respect to the pilot certificates, safety agenda, and the written test for the pilot certificate, and operating efficiency.

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Comparison of Fault Current Limiting Characteristics According to Facility in Power System (전력계통의 사고전류 저감 설비별 특성 비교)

  • Park, Hyoung-Min;Choi, Hyo-Sang;Cho, Yong-Sun;Lim, Sung-Hun;Hwang, Jong-Sun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.05b
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    • pp.127-129
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    • 2005
  • We investigated the fault current limiting characteristics according to the various facilities in power system. Power systems are becoming larger and larger for meeting electric power demand. Therefore, the over-currents resulting from contingencies such as short circuits are increasing higher, which causes the ratings of circuit breakers(CBs) to increase. Upgrading or replacement of CBs is not difficult from the technical and economical point of view. Bus split is being adopted into a part of 154 kV power systems, but it has adverse effects such as overload to neighboring power systems, increased voltage fluctuation, and decreased power system stability. For 345 kV power systems, the bus split measure is not feasible and dc reactors are being suggested. The superconducting fault current limiter is a protection gear of new concept that limits fault current automatically in a few milliseconds. It can also provide the effect of CB capacity increase, relaxation of power machine criteria, enhancement in power system reliability, and flexible power system operation.

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Arc-Extinguishing Characteristics of A Rotary-Arc Gas Circuit Breaker (자력소호 가스차단부의 소호특성)

  • Shin, Young-June;Park, Kyong-Yop;Song, Ki-Dong
    • Proceedings of the KIEE Conference
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    • 1994.07b
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    • pp.1593-1598
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    • 1994
  • Recently rotary-arc, thermal expansion and their composite interrupters are widely used in the distribution power system because they have lots of advantages in making the larger interrupting capacity, the smaller size, the lighter weight and the less surge. A model interrupter of rotary-arc type, which has constant stroke and thermal expansion volume, was studied by varying the design parameters, i.e. the number of turns of the driving coil, the inner diameter of the moving contact, the gas pressure and the shape of the fixed contact for this project. Short cicuit current interrupting tests were conducted to the model interrupters by varying the requirements from 42% to 175% of the test voltage, interrupting current and transient recovery voltage for the test duty No.4 of 7.2kV 12.5kA single phase test. The pressure rise, minimum and maximum arcing times were analyzed for each model interrupter. All types of model interrupters showed good interrupting performances and sufficient design margins for the ratings.

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Modeling and Analysis of the Micro-Grid with SVPWM Micro-Sources (SVPWM 방식 마이크로소스로 구성된 마이크로그리드 모델링 및 해석)

  • Son, Kwang-Myung;Lee, Kye-Byung;Kim, Young-Seob
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.20 no.3
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    • pp.12-19
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    • 2006
  • Micro-source units having power ratings in thousands of watts can provide power quality with higher reliability and efficiency than the conventional large scale units. This paper develops switching level model of micro-source and studies the characteristics of the micro-grid consisting of multiple micro-sources and interfaced with electric power system. The developed model adopts the space vector PWM to fully utilize the capacity of inverter. The interaction of the grid connected micro-sources and the characteristics of the control system parameters are investigated. Micro-sources and micro-grid are implemented using PSCAD/EMTDC. Simulation results show that the proposed model is efficient for studying micro-grid system.

An Estimation of power capacity for electric motor scooter (전동스쿠터의 필요 동력 용량 계산)

  • Kim, Moonhwan
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2009.10a
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    • pp.847-849
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    • 2009
  • Usually, after the decisions of the performance and range in the commercial vehicle, it is designed the ratings of the electric and mechanical elements for the vehicles. In this paper, the given performance and driving conditions, which are the maximum velocity, mileage, total weight of the normal gasoline scooter, battery type and size, and so on, are analysed for the design of the electric scooter. The maximum rotational speed and needed torque values of the electric motor which is substituted for the gasoline engine are calculated. These values can help to calculate the rating of the electric motor. In the calculation to obtain the torque and speed values, battery discharge and the running resistances are considered. We can decide the electric motor current value from the torque and speed values. The electric motor current values, which are significant parameter to decide the motor type and dimensions and characteristics of the electric motor, are decided by numerical simulation by the above conditions.

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The Prediction of DEA based Efficiency Rating for Venture Business Using Multi-class SVM (다분류 SVM을 이용한 DEA기반 벤처기업 효율성등급 예측모형)

  • Park, Ji-Young;Hong, Tae-Ho
    • Asia pacific journal of information systems
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    • v.19 no.2
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    • pp.139-155
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    • 2009
  • For the last few decades, many studies have tried to explore and unveil venture companies' success factors and unique features in order to identify the sources of such companies' competitive advantages over their rivals. Such venture companies have shown tendency to give high returns for investors generally making the best use of information technology. For this reason, many venture companies are keen on attracting avid investors' attention. Investors generally make their investment decisions by carefully examining the evaluation criteria of the alternatives. To them, credit rating information provided by international rating agencies, such as Standard and Poor's, Moody's and Fitch is crucial source as to such pivotal concerns as companies stability, growth, and risk status. But these types of information are generated only for the companies issuing corporate bonds, not venture companies. Therefore, this study proposes a method for evaluating venture businesses by presenting our recent empirical results using financial data of Korean venture companies listed on KOSDAQ in Korea exchange. In addition, this paper used multi-class SVM for the prediction of DEA-based efficiency rating for venture businesses, which was derived from our proposed method. Our approach sheds light on ways to locate efficient companies generating high level of profits. Above all, in determining effective ways to evaluate a venture firm's efficiency, it is important to understand the major contributing factors of such efficiency. Therefore, this paper is constructed on the basis of following two ideas to classify which companies are more efficient venture companies: i) making DEA based multi-class rating for sample companies and ii) developing multi-class SVM-based efficiency prediction model for classifying all companies. First, the Data Envelopment Analysis(DEA) is a non-parametric multiple input-output efficiency technique that measures the relative efficiency of decision making units(DMUs) using a linear programming based model. It is non-parametric because it requires no assumption on the shape or parameters of the underlying production function. DEA has been already widely applied for evaluating the relative efficiency of DMUs. Recently, a number of DEA based studies have evaluated the efficiency of various types of companies, such as internet companies and venture companies. It has been also applied to corporate credit ratings. In this study we utilized DEA for sorting venture companies by efficiency based ratings. The Support Vector Machine(SVM), on the other hand, is a popular technique for solving data classification problems. In this paper, we employed SVM to classify the efficiency ratings in IT venture companies according to the results of DEA. The SVM method was first developed by Vapnik (1995). As one of many machine learning techniques, SVM is based on a statistical theory. Thus far, the method has shown good performances especially in generalizing capacity in classification tasks, resulting in numerous applications in many areas of business, SVM is basically the algorithm that finds the maximum margin hyperplane, which is the maximum separation between classes. According to this method, support vectors are the closest to the maximum margin hyperplane. If it is impossible to classify, we can use the kernel function. In the case of nonlinear class boundaries, we can transform the inputs into a high-dimensional feature space, This is the original input space and is mapped into a high-dimensional dot-product space. Many studies applied SVM to the prediction of bankruptcy, the forecast a financial time series, and the problem of estimating credit rating, In this study we employed SVM for developing data mining-based efficiency prediction model. We used the Gaussian radial function as a kernel function of SVM. In multi-class SVM, we adopted one-against-one approach between binary classification method and two all-together methods, proposed by Weston and Watkins(1999) and Crammer and Singer(2000), respectively. In this research, we used corporate information of 154 companies listed on KOSDAQ market in Korea exchange. We obtained companies' financial information of 2005 from the KIS(Korea Information Service, Inc.). Using this data, we made multi-class rating with DEA efficiency and built multi-class prediction model based data mining. Among three manners of multi-classification, the hit ratio of the Weston and Watkins method is the best in the test data set. In multi classification problems as efficiency ratings of venture business, it is very useful for investors to know the class with errors, one class difference, when it is difficult to find out the accurate class in the actual market. So we presented accuracy results within 1-class errors, and the Weston and Watkins method showed 85.7% accuracy in our test samples. We conclude that the DEA based multi-class approach in venture business generates more information than the binary classification problem, notwithstanding its efficiency level. We believe this model can help investors in decision making as it provides a reliably tool to evaluate venture companies in the financial domain. For the future research, we perceive the need to enhance such areas as the variable selection process, the parameter selection of kernel function, the generalization, and the sample size of multi-class.

The Effects of Immunocastration on Meat Quality and Sensory Properties of Pork Bellies

  • Jeong, Jong-Youn;Choi, Ji-Hun;Choi, Yun-Sang;Han, Doo-Jeong;Kim, Hack-Youn;Lee, Mi-Ai;Lee, Duk-Hun;Kim, Cheon-Jei
    • Food Science of Animal Resources
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    • v.31 no.3
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    • pp.372-380
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    • 2011
  • This study was conducted to assess meat quality and sensory properties of pork bellies from immunocastrated males (IC) compared to meat from surgically castrated males (SC), intact males (IM), and females (FE). Pork bellies from IC had significantly higher pH values than meat from either SC or FE. Pork bellies from IC showed lower CIE $L^*$ values than those from SC, but were redder (higher CIE $a^*$ values) than meat from SC or FE. However, no differences in visual color were observed between pork bellies from IC and SC pigs using National Pork Producer Council scales. Water holding capacity was higher in SC and FE than that in IC. IC showed no significant difference in cooking loss and shear force values compared with those of SC. Both SC and IC had improved fat content when compared to that in IM, and IC meat showed a similar fat content to that of FE. Pork bellies from IC showed higher ratings for all visual evaluation traits than those of SC and were the same as meat from FE. Boar odor was not significantly different among the treatments. IC was rated similar to SC for taste, tenderness, and overall acceptability.